Dot-sight device with polarizers

ABSTRACT

Disclosed is a dot-sight device with polarizers. The dot-sight device with polarizers includes: a reflecting mirror; a first polarizing unit provided in front of the reflecting mirror; a dot indication generator emitting a ray to the reflecting mirror to form a the dot virtual image; and a second polarizing unit provided in front of the dot indication generator, the first polarizing unit and the second polarizing unit being arranged so that a ray of the dot indication generator is passed through the second polarizing unit but blocked by the first polarizing unit. Thus, there is provided a dot-sight device with polarizers, in which a ray emitted from a dot indication generator is not discovered by the other party and thus a dot-sight observer is not discovered by the other party.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No.10-2011-0121802, filed Nov. 21, 2011, which is hereby incorporated byreference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a dot-sight device with polarizers, andmore particularly to a dot-sight device with polarizers, in which a rayemitted from a dot indication generator is not discovered by the otherparty, and thus a dot-sight observer is not discovered by the otherparty.

2. Description of the Related Art

The features of guns such as a rifle, a heavy machine gun, etc. dependon how quick an aimed shot is fired and how accurate a target is aimed.In general, the aiming of the guns is achieved by aligning a line ofsight between the gun-sight and the foresight. The aiming based onalignment of the line of sight between the foresight located at an endof a gun barrel and the gun-sight located at a top of a gun body makessharpshooting be possible according to abilities of an observer who usesthe gun.

However, in the case of the aiming based on only the gun-sight and theforesight, even minor variation and shaking make it difficult to alignthe line of sight, and also short-distance firing or urgent situationmake it difficult to do quick aiming.

That is, such an aimed-shot method requires complicated processes suchas target capture and confirmation, alignment in the light of sight,aiming, etc. and requires time. Further, the foresight and the gun-sightare so small that accurate alignment therebetween is susceptible tominor shaking Moreover, if too much attention is paid to the alignmentin the line of sight, the attention is drawn to the foresight and thegun-sight rather than a target or a front view and therefore visionneeded for shooting or urgent situations becomes narrower.

To solve the foregoing problems, a dot-sight device has been proposed.The dot-sight device employs a lens of no magnification or lowmagnification in an optical sight, and uses a simple dot instead of acomplicated line of sight.

The dot-sight device of optical no-magnification (low magnification)enables the simple and quick sight and it very useful in urgentsituations or short distance. Specifically, it is possible to save timetaken in conventional alignment in the line of sight, and the sight isachieved by positioning a dot (virtual image) on a target. Thus, anobserver can afford to secure a view. Consequently, it is possible toquickly and accurately adjust a sight, and to secure a circumferentialview needed for determining situations.

In detail, as shown in FIG. 1, a conventional dot-sight device 1 havinga singlet reflecting mirror is fastened to a gun through a fasteninggrill 11, and is aligned with the gun barrel through a gun main scopetube aligning terminal 3. Then, a virtual dot provided to an observer,caused as a ray of a dot indication generator 5 is reflected from thereflecting mirror 7, is positioned on a target point, so that s/he canconfirm the sight. Generally, a front (facing an observer in thedot-sight device 1) of the reflecting mirror 7 is coated to reflect theray emitted from the dot indication generator 5, and the front and rearcurvatures of the reflecting mirror 7 have spherical surfaces oraspheric surfaces.

An observer fires a shot when the virtual dot reflected from thereflecting mirror 7 is positioned on a gazing target point by nomagnification through a protective window 9, that is, when the virtualimage of the dot is aligned with the target. Thus, it is easy to adjustthe sight.

However, in the case of the conventional dot-sight device, as shown inFIG. 1, a dot indication generator 5 is located in a place where most ofthe ray reflected from the reflecting mirror 7 travels withoutinterference, and therefore the ray emitted from the dot indicationgenerator 5 is not seen outside, thereby preventing an dot-sightobserver from being discovered by the other party around the target. Tothis end, an optical axis of the reflecting mirror 7 has to be inclinedat a certain angle (i.e., A1 of FIG. 2( a); a1 is generally a half of A2formed by a path where a principal ray emitted from the dot indicationgenerator is reflected from the reflecting mirror and travels toward adot-sight optical axis) with respect to a representative ray (i.e., aprincipal ray: which is a center ray among the reflected rays andaligned with an optical axis of the dot sight) of the rays reflectedfrom the reflecting mirror 7 and constituting the dot (i.e., an virtualimage of dot indication from the reflecting mirror).

Then, as shown in (a) and (b) of FIG. 2, the arrangement of thereflecting mirror inclined with respect to the dot sight optical axis(refer to FIG. 2( a)) causes a finite ray aberration to be greater thanthat in the arrangement of the reflecting mirror not inclined withrespect to the dot sight optical axis (refer to FIG. 2( b)), therebyhaving an effect on parallax of the dot to be observed by an observer.Also, the size (diameter) of the reflecting mirror and the dotindication generator are compared in the parallax under conditionshaving the same distance from the reflecting mirror, the arrangement ofthe reflecting mirror inclined with respect to the dot sight opticalaxis (refer to FIG. 2( a)) causes the parallax to be greater than thatin the arrangement of the reflecting mirror not inclined with respect tothe dot sight optical axis (refer to FIG. 2( b)).

The great parallax causes an error to become larger as a visual axis ofan observer to a shooting target point in the reflecting mirror goesbeyond the dot sight optical axis and gets closer to vicinity, withrespect to an initial alignment state among an optical axis of thedot-sight device, a bullet shooting axis of the gun barrel, and thetarget point. Naturally, the excessive parallax deteriorates a hitdegree to the target when the dot sight is used. In other words, thesize of the reflecting mirror is limited by an inclined angle A1 of thereflecting mirror, in which the size of the reflecting mirror has toprovide the parallax within a certain limit (i.e., a degree of parallaxwhere a degree of deviation between the position of the target point andthe position of the dot (an virtual image of the dot indication) iswithin the limit of eye's resolutions or within a shooting errorreference).

However, if the dot indication generator is arranged as shown in (b) ofFIG. 2 in order to prevent the excessive parallax, the ray emitted fromthe dot indication generator may be observed by the other party aroundthe target, and it is thus not preferable.

Also, as shown in FIG. 3, the conventional dot sight has the reflectingmirror 7 of which curvature is designed depending on D1 and D2 (forexample, a singlet mirror has two reflecting surfaces, and doubletmirrors has four reflecting surfaces (two reflecting surface among whichhave the same curvature)). Here, D1 is a horizontal distance in anoptical axial direction of the dot sight from the optical center of thereflecting mirror 7 to the dot indication of the dot indicationgenerator 5, and D2 is a vertical distance in the optical axialdirection of the dot sight from the optical center of the reflectingmirror 7 o the inside of the dot sight housing 10 in a direction wherethe dot indication generator 5 is installed.

Particularly, the conventional dot sight cannot make the verticaldistance at the position of the dot indication generator 5 in the dotsight optical axis C1 be shorter than D2 in order to prevent the raysemitted from the dot indication generator 5 from being exposed to theother party, and thus cannot make an angle between the optical axis C2of the reflecting mirror and the optical axis C1 of the dot sight besmaller than A1 determined by D1 and D2

$( {{A\; 1} = \frac{\tan^{- 1}( \frac{D\; 2}{D\; 1} )}{2}} ).$

Since the reflecting mirror inclined with respect to the dot sightoptical axis has a finite ray aberration larger than that of thereflecting mirror not inclined with respect to the dot sight opticalaxis, the parallax around the reflecting mirror of the dot sight becomeslarger.

Also, as shown in FIG. 1, the conventional arrangement of the dotindication generator allows the ray of the dot indication generator tobe not seen at great distances in a close observation optical axisdirection V1 of the dot sight so that an observer cannot be discoveredby the other party around the target. However, the ray emitted by thedot indication generator of the dot sight in this case can be observedby the other party who gets out of the dot sight optical axis, forexample, who is located at close distances in a direction of V2.Accordingly, it is disadvantageously impossible to fully prevent anobserver of the dot sight from being exposed.

BRIEF SUMMARY

Accordingly, the present invention is conceived to solve the forgoingproblems, and an aspect of the present invention is to provide adot-sight device with polarizers, in which it is possible to not onlyprevent the ray emitted from the dot indication generator from beingobserved at the other party and thus prevent an observer from beingdiscovered by the other party, but also freely design an angle betweenthe dot indication of the dot indication generator and the optical axisof the dot sight on the reflecting mirror, thereby providing thedot-sight device with the polarizers, which can decrease the parallax ofthe reflecting mirror.

Also, an aspect of the present invention is to provide a dot-sightdevice with polarizers, in which even through the dot indicationgenerator is arranged on the window arranged in front of the reflectingmirror in order to minimize the parallax of the reflecting mirror, it ispossible to prevent the ray of the dot indication generator from beingobserved by the other party through the polarization member. Therefore,under the same distance from the reflecting mirror to the dot indicationgenerator, it is possible to use the reflecting mirror larger than thatof the conventional dot sight within a degree of parallax allowable inthe existing dot sight. Further, under the same size of the reflectingmirror, it is possible to make the distance from the reflecting mirrorto the dot indication generator be shorter than that of the conventionaldot sight.

Further, an aspect of the present invention is to provide a dot-sightdevice with polarizers, in which if the ray of the dot indicationgenerator is allowed to be exposed to the other party, it is possible toseparate and remove the first polarizing unit from the front of thereflecting mirror, thereby securing sufficient quantity of incidentlight from the exterior as necessary.

One aspect of the present invention provides a dot-sight device withpolarizers, comprising: a reflecting mirror; a first polarizing unitprovided in front of the reflecting mirror; a dot indication generatoremitting a ray to the reflecting mirror to form a the dot virtual image;and a second polarizing unit provided in front of the dot indicationgenerator, the first polarizing unit and the second polarizing unitbeing arranged so that a ray of the dot indication generator is passedthrough the second polarizing unit but blocked by the first polarizingunit.

The first polarizing unit may be detachably assembled in front of thereflecting mirror.

The first polarizing unit and the second polarizing unit may includelinear polarizers of which polarization directions are orthogonal toeach other, or circular polarizers of which circular polarizationdirections are counter to each other.

The dot-sight device with the polarizers may further comprise a windowwhich is arranged in rear of the reflecting mirror and to which the dotindication generator is fastened.

The dot indication generator may be provided in an area, where thereflecting mirror is projected in an optical axial direction of the dotsight, on the window.

The window may be formed with a transparent electrode circuit line tosupply electric power to the dot indication generator.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or other aspects of the present invention will becomeapparent and more readily appreciated from the following description ofthe exemplary embodiments, taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a view schematically showing an internal configuration of ageneral dot-sight device,

FIG. 2 is a concept view showing a degree of parallax according topositions of a dot indication generator,

FIG. 3 is a cross-section view of a conventional dot-sight device,

FIG. 4 is a perspective view of a dot-sight device with polarizersaccording to an embodiment of the present invention,

FIG. 5 is a rear perspective view of the dot-sight device with thepolarizers according to an embodiment of the present invention,

FIG. 6 is a cross-section view of the dot-sight device with thepolarizers according to an embodiment of the present invention,

FIG. 7 shows cross-section views of the dot-sight device with thepolarizers according to other embodiments of the present invention,

FIG. 8 is a front view showing a window side in (c) of FIG. 7, and

FIG. 9 is a cross-section view showing another embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Prior to description, like numerals will refer to like elements throughmany exemplary embodiments, which are representatively described in anexemplary embodiment, and the other exemplary embodiments describe onlydifferent configurations.

Below, a dot-sight device with polarizers according to a firstembodiment of the present invention will be described with reference toaccompanying drawings.

Among the accompanying drawings, FIG. 4 is a perspective view of adot-sight device with polarizers according to an embodiment of thepresent invention, FIG. 5 is a rear perspective view of the dot-sightdevice with the polarizers according to an embodiment of the presentinvention, and FIG. 6 is a cross-section view of the dot-sight devicewith the polarizers according to an embodiment of the present invention.

As shown therein, the dot-sight device with the polarizers according toan embodiment of the present invention includes a housing 110 formedwith a main scope tube having a first end portion facing a target and asecond end portion facing an observer; a reflecting mirror 120 formed inthe first end portion of the main scope tube; a first polarizing unit130 provided in front of the reflecting mirror 120; a dot indicationgenerator 140 provided in the second end portion of the main scope tube;and a second polarizing unit 150 provided in front of the dot indicationgenerator 140.

The housing 110 is internally formed with a closed or opened main scopetube and installed in a firearm such as guns or the like. Between thehousing 110 and the firearm may be provided a zero adjuster that finelyadjusts the position of the housing 110 in up, down, left and rightdirections.

The reflecting mirror 120 is provided in the first end portion of themain scope tube of the housing 110, and transmits an image of the targetwhile reflecting the ray provided by the dot indication generator 140toward an observer. An observer positions a virtual image of dotindication reflected from the reflecting mirror 120 on to the target soas to adjust the sight. The reflecting mirror 120 may be achieved by asinglet reflecting mirror 120 applied to a typical dot sight, a doubletreflecting mirror 120 disclosed in Korean Patent No. 10-0667472, titledof ‘dot sight’, or the likes.

The dot indication generator 140 is configured to have a light emittingmeans and a transparent reticle located at a front end of the lightemitting means and forming the dot indication by transmitting the rayemitted from the light emitting means, or is configured to form the dotindication by activating a pixel like an OLED, an LED, an LCOS. Here,the transparent reticle has a pivotal structure and allows the kind ofdot indication to be selected according to the kinds or distances of thetarget. If the dot indication generator 140 is achieved by the OLED, theLED, the LCOS, etc., it may be possible to activate a pixel at a desiredposition and finely adjust the shape or position of the dot.

The first polarizing unit 130 and the second polarizing unit 150 arerespectively provided in front of the reflecting mirror 120 and the dotindication generator 140. If the first polarizing unit 130 and thesecond polarizing unit 150 are achieved by the linear polarizers, theyare arranged to have polarization directions orthogonal to each other.If the first polarizing unit 130 and the second polarizing unit 150 areachieved by the circular polarizers, they are arranged to have circularpolarization directions counter to each other.

In general, the circular polarizer is configured by combination of thelinear polarizer and a quarter-wave plate. Thus, if the first polarizingunit 130 and the second polarizing unit 150 are configured by the linearpolarizer and the circular polarizer, the linear polarizer constitutingthe first polarizing unit 130 and the linear polarizer of the circularpolarizer constituting the second polarizing unit 150 are arranged toface each other while the polarization directions of the linearpolarizers opposite to each other are perpendicular to each other,thereby preventing the ray of the dot indication generator 140 fromtraveling outwards. Also, if the first polarizing unit 130 and thesecond polarizing unit 150 are configured by a pair of circularpolarizer, the linear polarizers respectively provided in the pair ofcircular polarizers are arranged to face each other while thepolarization directions of the linear polarizers opposite to each otherare perpendicular to each other, thereby preventing the ray of the dotindication generator 140 from traveling outward.

In this embodiment, the first polarizing unit 130 and the secondpolarizing unit 150 are achieved by the pair of linear polarizers ofwhich polarization directions are orthogonal to each other or by thepair of circular polarizers of which the circular polarizationdirections are counter to each other, but not limited thereto.Alternatively, combination of at least two polarizing units may be usedto prevent the ray of the dot indication generator 140 from travelingoutward.

Now, operations of the dot-sight device with the polarizers according tothe first embodiment will be described.

As shown in FIG. 6, in the dot-sight device with the polarizersaccording to the first embodiment, the first polarizing unit 130 and thereflecting mirror 120 are installed in turn from the outside to thefirst end portion located in front of the main scope tube of the housing110, the dot indication generator 140 is installed to the second endportion in a direction facing the reflecting mirror 120, and the secondpolarizing unit 150 is installed in front of the dot indicationgenerator 140.

The dot indication generator 140 may have a structure capable of formingthe dot indication by activating the pixel like the OLED, LCD, LCOS,etc., or may have a structure including the light emitting means and thetransparent reticle located at the front end of the light emitting meansand forming the dot indication by transmitting the ray emitted from thelight emitting means.

The housing 110, where the dot indication generator 140 and thereflecting mirror 120 are installed, is fastened to the guns (not shown)such as a mount for a heavy machine gun and adjusted in a zero point bythe zero adjuster. Then, an observer confirms an external target throughthe first polarizing unit 130 and the reflecting mirror 120. At thistime, the ray emitted from the dot indication generator 140 is reflectedfrom the reflecting mirror 120 and enters an observer's eyes. The dotindication reflected from the reflecting mirror 120 forms a virtualimage of a dot, and is recognized by an observer.

If the first polarizing unit 130 and the second polarizing unit 150 arethe linear polarizers, the ray emitted from the dot indication generator140 is converted into the ray of the linear polarized light having acertain direction while passing through the second polarizing unit 150.Then the polarized ray is reflected from the reflecting mirror 120 andobserved by an observer's eyes in the form of a dot virtual image.However, the polarization direction of the ray emitted from the dotindication passed through the reflecting mirror 120 is orthogonal to thepolarization direction of the ray capable of passing through the firstpolarizing unit 130, and thus blocked without traveling outward.

Also, if the first polarizing unit 130 and the second polarizing unit150 are the circular polarizers, the ray emitted from the dot indicationgenerator 140 is converted into the ray of the circular polarized lighthaving a certain circular direction (e.g., rightward rotation) whilepassing through the second polarizing unit 150. Then the polarized rayis reflected from the reflecting mirror 120 and observed by anobserver's eyes in the form of a dot virtual image. However, thepolarization direction of the ray emitted from the dot indication passedthrough the reflecting mirror 120 is counter to the polarizationdirection (e.g., leftward rotation) of the ray capable of passingthrough the first polarizing unit 130, and thus blocked withouttraveling outward. Thus, in the state that the first polarizing unit 130and the second polarizing unit 150 are installed as above, the raygenerated by the dot indication generator 140 cannot pass through thefirst polarizing unit 130 provided in front of the reflecting mirror120, thereby preventing the ray of the dot indication generator 140 frombeing observed by the other party and preventing an observer from beingdiscovered.

Here, the first polarizing unit 130 and the second polarizing unit 150maybe configured by coating a glass plate to have polarizing ability orattaching a polarizing film to the glass plate. Alternatively, they maybe achieved by various methods, for example by inserting the polarizingfilm in between two glass plates, by a thick polarizing film, or etc.

Next, the dot-sight device with the polarizers according to a secondembodiment of the present invention swill be described.

Among the accompanying drawings, FIG. 7 shows cross-section views of thedot-sight device with the polarizers according to other embodiments ofthe present invention, and FIG. 8 is a front view showing a window sidein (c) of FIG. 7.

As shown in FIG. 7, this embodiment of the dot-sight device with thepolarizers is different from the foregoing embodiment in that thehousing 110 is a close type dot sight as opposed to the foregoing opentype housing 110, a window 160 is arranged at a portion opposite to anobserver's eyes, the dot indication generator 140 is fastened to thewindow 160, and the second polarizing unit 150 is provided in front ofthe dot indication generator 140.

(a) to (c) of FIG. 7 shows different positions where the dot indicationgenerator 140 are located. Here, (a) of FIG. 7 shows that the dotindication generator 140 is arranged at the same position as that of thefirst embodiment; (b) shows that the dot indication generator 140 isarranged on the window 160 as being closer to the dot sight optical axisthan that in (a) of FIG. 7, in which the ray emitted from the dotindication in the conventional dot sight is seen to the other partylocated in front of the dot sight; and (c) shows that the dot indicationgenerator 140 is located at a position through which the optical axis ofthe dot sight can pass. Here, the parallax of the reflecting mirror 120becomes smaller in order of (a), (b) and (c).

As shown in (b) and (c) of FIG. 7, even through the dot indicationgenerator 140 is arranged to be adjacent to the dot sight optical axison the window 160, or arranged on the position where the dot sightoptical axis passes so as to decrease the parallax of the reflectingmirror 120, the ray of the dot indication generator 140 passed throughthe second polarizing unit 150 is blocked by the first polarizing unit130 arranged in front of the reflecting mirror 120, so that the rayemitted from the dot indication generator 140 cannot be discovered bythe other party around the target.

That is, in the dot-sight device with the polarizers according to thepresent invention, the dot indication generator 140 can beadvantageously installed at an arbitrary position on the window 160within the area where the reflecting mirror 120 is projected in anoptical axis direction.

Also, not only when the dot indication generator according to thepresent invention is installed at the same position as the conventionaldot sight, but also when the dot indication generator according to thepresent invention is installed to be closer to the dot sight opticalaxis on the window 160 as shown in (b) and (c) of FIG. 7, the ray of thedot indication generator 140 is blocked by the first polarizing unit 130and the second polarizing unit 150. Therefore, under the same distancefrom the reflecting mirror 120 to the dot indication generator 140, itis possible to use the reflecting mirror 120 larger than that of theconventional dot sight within a degree of parallax allowable in theexisting dot sight. Further, under the same size of the reflectingmirror 120, it is possible to make the distance from the reflectingmirror 120 to the dot indication generator 140 be shorter than that ofthe conventional dot sight.

That is, in the dot-sight device with the polarizers according to anembodiment of the present invention, the ray generated by the dotindication generator 140 is not exposed to the other party and thereforethere is no limit to an angle between the optical axis of the reflectingmirror and the optical axis of the dot sight. Accordingly, if this angleis 0 as shown in (c) of FIG. 6, it is possible to configure the dotsight having the minimum parallax of the reflecting mirror among the dotsights having the same d1 and d2 as those of the conventional dot sight.

FIG. 8 shows that the dot indication generator 140 is attached andfastened to the window 160, in which the transparent electrode circuitline 170 (generally, a power supplying line) of the dot indicationgenerator 140 may use a transparent electrode such as indium-tin oxide(ITO) attached to the window 160. If a signal or electric power issupplied by connecting edges of the dot indication generator 140 and thewindow 160 through the transparent electrode circuit line 170, it may bepossible to observe an external target in a rear window area except thedot indication generator 140.

Further, according to still another embodiment of FIG. 8, the foregoingfirst polarizing unit 130 is mounted to a cap housing 111 shaped like acap and coupled to the housing 110 in front of the reflecting mirror 120by a detachable structure using an uneven groove. Thus, if the ray ofthe dot indication generator 140 has to be prevented from being exposedto the other party, the first polarizing unit 130 may be attached infront of the reflecting mirror 120. On the other hand, if the rayemitted by the dot indication generator 140 is allowed to be exposed tothe other party, the first polarizing unit 130 together with the caphousing 111 is separated from the front view of the reflecting mirror120, thereby securing, thereby additionally securing the quality ofincident light from the exterior. Of course, there may be variousmethods of detaching and attaching the cap housing 111 mounted with thefirst polarizing unit 130.

According to an embodiment of the present invention, it is possible tonot only prevent the ray emitted from the dot indication generator frombeing observed at the other party and thus prevent an observer frombeing discovered by the other party, but also freely design an anglebetween the dot indication of the dot indication generator and theoptical axis of the dot sight on the reflecting mirror, therebyproviding the dot-sight device with the polarizers, which can decreasethe parallax of the reflecting mirror.

Also, even through the dot indication generator is arranged on thewindow arranged in front of the reflecting mirror in order to minimizethe parallax of the reflecting mirror, it is possible to prevent the rayof the dot indication generator from being observed by the other partythrough the polarization member. Therefore, under the same distance fromthe reflecting mirror to the dot indication generator, it is possible touse the reflecting mirror larger than that of the conventional dot sightwithin a degree of parallax allowable in the existing dot sight.Further, under the same size of the reflecting mirror, it is possible tomake the distance from the reflecting mirror to the dot indicationgenerator be shorter than that of the conventional dot sight.

Further, if the ray of the dot indication generator is allowed to beexposed to the other party, it is possible to separate and remove thefirst polarizing unit from the front of the reflecting mirror, therebysecuring sufficient quantity of incident light from the exterior asnecessary.

While this invention has been described in connection with what ispresently considered to be practical exemplary embodiments, it is to beunderstood that the invention is not limited to the disclosedembodiments, but, on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims.

What is claimed is:
 1. A dot-sight device with polarizers, comprising: areflecting mirror; a first polarizing unit provided in front of thereflecting mirror; a dot indication generator emitting a ray to thereflecting mirror to form a the dot virtual image; and a secondpolarizing unit provided in front of the dot indication generator, thefirst polarizing unit and the second polarizing unit being arranged sothat a ray of the dot indication generator is passed through the secondpolarizing unit but blocked by the first polarizing unit.
 2. Thedot-sight device with polarizers according to claim 1, wherein the firstpolarizing unit is detachably assembled in front of the reflectingmirror.
 3. The dot-sight device with polarizers according to claim 1,wherein the first polarizing unit and the second polarizing unitcomprise linear polarizers of which polarization directions areorthogonal to each other, or circular polarizers of which circularpolarization directions are counter to each other.
 4. The dot-sightdevice with polarizers according to claim 1, further comprising a windowwhich is arranged in rear of the reflecting mirror and to which the dotindication generator is fastened.
 5. The dot-sight device withpolarizers according to claim 4, wherein the dot indication generator isprovided in an area, where the reflecting mirror is projected in anoptical axial direction of the dot sight, on the window.
 6. Thedot-sight device with polarizers according to claim 5, wherein thewindow is formed with a transparent electrode circuit line to supplyelectric power to the dot indication generator.
 7. The dot-sight devicewith polarizers according to claim 2, further comprising a window whichis arranged in rear of the reflecting mirror and to which the dotindication generator is fastened.
 8. The dot-sight device withpolarizers according to claim 7, wherein the dot indication generator isprovided in an area, where the reflecting mirror is projected in anoptical axial direction of the dot sight, on the window.
 9. Thedot-sight device with polarizers according to claim 8, wherein thewindow is formed with a transparent electrode circuit line to supplyelectric power to the dot indication generator.
 10. The dot-sight devicewith polarizers according to claim 3, further comprising a window whichis arranged in rear of the reflecting mirror and to which the dotindication generator is fastened.
 11. The dot-sight device withpolarizers according to claim 10, wherein the dot indication generatoris provided in an area, where the reflecting mirror is projected in anoptical axial direction of the dot sight, on the window.
 12. Thedot-sight device with polarizers according to claim 11, wherein thewindow is formed with a transparent electrode circuit line to supplyelectric power to the dot indication generator.